Publications by authors named "C M. Laymon"
Introduction: Alzheimer's disease (AD) in Down syndrome (DS) is associated with changes in brain structure. It is unknown if thickness and volumetric changes can identify AD stages and if they are similar to other genetic forms of AD.
Methods: Magnetic resonance imaging scans were collected for 178 DS adults (106 nonclinical, 45 preclinical, and 27 symptomatic).
Background: The relationship between subtle cognitive decline and Alzheimer's disease (AD) pathology as measured by biomarkers in settings outside of specialty memory clinics is not well characterized.
Objective: To investigate how subtle longitudinal cognitive decline relates to neuroimaging biomarkers in individuals drawn from a population-based study in an economically depressed, small-town area in southwestern Pennsylvania, USA.
Methods: A subset of participants without dementia (N = 115, age 76.
Introduction: Adults with Down syndrome demonstrate striatum-first amyloid accumulation with [C]PiB PET imaging, which has not been replicated with [F]florbetapir (FBP). Early striatal accumulation has not been temporally quantified with respect to global cortical measures.
Methods: Longitudinal PiB (n=175 participants) and FBP (n=92 participants) data from the Alzheimer Biomarkers Consortium-Down Syndrome were used to measure cortical and striatal binding.
Article Synopsis
- This study focused on the risk of Alzheimer's disease in adults with Down syndrome, using amyloid and tau PET imaging to track disease progression.
- It involved a longitudinal analysis of 167 participants, assessing cognitive functioning and biomarkers over two visits between 2017 and 2022.
- The research aimed to determine the timeline for symptomatic Alzheimer's based on "amyloid age" and its relation to cognitive decline and tau accumulation.
Article Synopsis
- - Individuals with Down syndrome (DS) face a high risk of developing Alzheimer's disease (AD), but about 20% do not show dementia symptoms until later in life, potentially due to the presence of mosaicism, which can reduce gene expression from chromosome 21.
- - Researchers analyzed data from two major studies (ABC-DS and a legacy study) that included neuropsychological assessments and biomarkers to determine the prevalence and impact of mosaicism, finding it in less than 10% of participants.
- - Those with mosaicism exhibited lower levels of AD-related biomarkers and a slower decline in cognitive scores compared to individuals with full trisomy, indicating a potential protective effect against dementia, though more research is needed to fully understand these findings.